The use of integrated circuits in electronic devices has steadily increased in recent years. Integrated circuits contain a variety of electronic components which may include capacitors, resistors, transistors and other devices. The integrated circuits are fabricated in a substrate using complex fabrication processes that use an extensive amount of time and labor.
Many problems may exist during fabrication of capacitors in the integrated circuit. For example, metals used to form the underlying electrode on which a dielectric is grown react with a large number of chemical substances used in the fabrication processes (e.g. with the liquid or solid material of a resist layer, in particular a photoresist, or with liquids which are used to develop a resist layer). Additionally, the growth of a high quality dielectric, i.e. having low leakage currents, is dependent on whether the surface of the metal has not yet reacted with resist or developer.
Other problems with capacitor fabrication in integrated circuits include incomplete patterning of the dielectric and/or electrodes, inability in controlling the dielectric thickness, or formation of polymers on the sides of the dielectric which produce a contact (creepage path) between the electrodes. It would also be useful to decrease the number of process steps to reduce the fabrication cost.
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